package com.lxf.cn.app;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTDecodeException;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.auth0.jwt.impl.ClaimsHolder;
import com.lxf.cn.model.User;
import com.lxf.cn.redis.RedisUitls;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;

/**
 * Created by liaoxuefeng on 2018/12/6.
 */
public class AuthTokenFilter implements HandlerInterceptor {

    @Autowired
    RedisUitls redisUitls ;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object object) throws Exception {

        String token = request.getHeader("token");

        // 如果不是映射到方法直接通过
        if(!(object instanceof HandlerMethod)){
            return true;
        }
        HandlerMethod handlerMethod=(HandlerMethod)object;
        Method method=handlerMethod.getMethod();
        //检查是否有passtoken注释，有则跳过认证
        if (method.isAnnotationPresent(PassToken.class)) {
            PassToken passToken = method.getAnnotation(PassToken.class);
            if (passToken.required()) {
                return true;
            }
        }

        if (token == null) {
            throw new RuntimeException("无token，请重新登录");
        }

        //判断token redis 是否过期
        if (StringUtils.isBlank(redisUitls.getString("appTokne"))) {
            throw new RuntimeException("token已过期，请重新登录");
        }

        // 获取 token 中的 user id
        String userId ;
        try {
            userId = JWT.decode(token).getAudience().get(0);
        } catch (JWTDecodeException j) {
            throw new RuntimeException("用户不存在,请重新登录");
        }

        //查询用户是否存在数据库
      //  User user = userService.findUserById(userId);
        User user = new User();
        if (user == null) {
            throw new RuntimeException("用户不存在，请重新登录");
        }
        // 验证 token
        JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(user.getPassword())).build();
        try {
            jwtVerifier.verify(token);
        } catch (JWTVerificationException e) {
            throw new RuntimeException("token 无效");
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}
